Evidence of hyperdimensional topological defects in a ferroelectric supercrystal phase-transition

Feifei Xin; Fabrizio Di Mei; Ludovica Falsi; Davide Pierangeli; Galina Perepelitsa; Yehudit Garcia; Aharon J. Agranat; Eugenio DelRe

arXiv · 2104.06791

Evidence of hyperdimensional topological defects in a ferroelectric supercrystal phase-transition

Feifei Xin·Fabrizio Di Mei·Ludovica Falsi·Davide Pierangeli·Galina Perepelitsa·Yehudit Garcia·Aharon J. Agranat·Eugenio DelRe

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Abstract

We perform real-time stereoscopic wide-area imaging of a ferroelectric phase-transition in KTN:Li. Spontaneous polarization is observed to form a thermally hysteretic 3D lattice of mutually interlinked closed-flux patterns that spans the entire sample. Results are compatible with a supercrystal of $N=4$ topological texture defects arising as the three-fold spatial and one-fold time-inversion symmetries are simultaneously broken. Each lattice site of the texture supercrystal emerges as the projection in actual space of an S$^3$ hypersphere, an extended volume Hopf-link fabric able to screen both volume charge and ferroelectric strain.

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Feifei Xin, Fabrizio Di Mei, Ludovica Falsi, Davide Pierangeli, Galina Perepelitsa, Yehudit Garcia, Aharon J. Agranat, Eugenio DelRe. 2021-04-14. Evidence of hyperdimensional topological defects in a ferroelectric supercrystal phase-transition. https://arxiv.org/abs/2104.06791

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